
You misunderstand. In numerically small breeds any dogs siring more than a few litters may end up having disproportionate influence on the gene pool (popular sire syndrome).
A dog used more than a couple of times can easily end up being a 'popular sire', conversely some very good males, including champions, never get used, mainly because they may be too closely related to available bitches, so it hardly encourages anyone to pay for semen storage.
As you say to be worthwhile you would want to use semen for more than one litter to make it worthwhile.
When I have travelled to mate a bitch it was
1). to have a better chance of getting a litter both in size and success rate.
2).Knowing that only one or two of the resulting litter would be likely to be useful to me, or the gene pool.
3) We in the UK in our breed have had very little success with AI only two litters in 30 years, and many failures.
In my own breed I don't think everyone saves semen in the USA, certainly not in Scandinavia, and so the costs for semen would have to be borne by the importer. Also I think your veterinary charges are probably far more reasonable than most people pay. Years ago I paid £70 per premate test, and that was using the in-house kits.
So there is a lot to weigh up expense wise.
Importantly though I like to know that both dog and bitch still retain their natural mating behaviour/libido, so as not to store up difficulties for later genrations.